"You cannot have that lack of alignment if you're really behind the core goals."Melissa Beck

Melissa Beck, their executive director, said divesting from fossil fuels is a moral imperative. "Otherwise," she said, "it's like tying a weight to your foot. You're trying to take all these great steps forward. ...Yet your assets are keeping those companies afloat. It can't be that way. You cannot have that lack of alignment if you're really behind the core goals, and the core mission, of your foundation."

Divestment isn't limited only to big foundations. Cities are getting on board as well. So far, 22 cities across the country have divested from fossil fuel technology. Some are names you'd expect in places like Seattle, Washington and Portland, Oregon. But then there's New London.

Daryl Justin Finizio, the city's mayor, said, "The city of New London controls approximately $40 million in pension fund investments. The pension committee, which I chair, has voted to instruct our fund managers to divest any of those holdings from portfolios or corporations that have interests and investments in fossil fuel technologies."

Finizio said that about five percent of the city's overall investments will be shifted to more sustainable funds. "We've actually asked them to look at emergent technologies," he said, "which includes green tech, and to look at bioscience and medical technologies, which are the growing industries, particularly in the northeast and in the emergent markets. Those portfolios are performing as well as fossil fuel portfolios." The divestment debate is also playing out at Yale, where a student petition last November called for the university to partially divest its $20 billion endowment from fossil fuels. University officials said they are exploring the idea.